Troubleshooting and repairing your Commodore 128

452 Pages·1989·34.719 MB·English

by  Margolis, Art

ART MARGOLI
Troubleshootirig and Repairing Your
COMM ODoRE TM
12B

Troubleshooting and Repairing Your
COMMODORE"
12B
ART MARGOLIS
I I
TAB
TAB BOOKS Inc.
Blue Ridge Summit. PA
FIRST EDITION
FIRST PRINTING
Copyright © 1989 by TAB BOOKS Inc.
Printed in the United States of America
Reproduction or publication of the content in any manner, without express
permission of the publisher, is prohibited. No liability is assumed with respect to
the use of the information herein.
Library of Congress Cataloging in Publication Data
Margolis, Art.
Troubleshooting and Repairing Your Commodore 128 I by Art
Margolis.
p. cm.
Includes index.
ISBN 0-8306-9099-9 ISBN 0-8306-9399-8 (pbk.)
1. Commodore 128 (Computer) 2. Commodore 128 (Computer)
-Maintenance and repair. I. Title. II. Title: Trouble shooting
and repairing your Commodore 128.
QA76.8.C645M37 1988
621.391'6-dc19 88-20129
CIP
TAB BOOKS Inc. offers software for
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Blue Ridge Summit, PA 17294-0850.
Questions regarding the content of this book
should be addressed to:
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TAB BOOKS Inc.
Blue Ridge Summit, PA 17294-0214
Contents
viii
ix
1 C128 Briefing Session 1
The Symptom Devices-Diagnostic Programming-Printboard Landmarks-An Overview of Trouble
Analysis
2 lDisassembliy 20
Getting the Hood Up-Freeing the Printboard-The Power Supply Box-Visual Repairs-Cleaning
Static Electricity
3 Chip locatioln Guide 39
Specific Information-Chip Survey
4 Chip Changing Teclhl8'1li«~LIles 49
The Rugged Chips-Tristating TTLs-The Sensitive Chips-The DIP Package-Socketed Chips
Soldered-in Chips
5 The lSI Chips 157
The Microprocessors-The 6526 Complex Interface Adapters-The VIC and Video Controller
Chips-6581 Sound Interface Device-The PLA and MMU
6 Dynamic Rall'lldom Access Memory 86
Static RAM-Dynamic RAM
7 Read OrDly Memory 104
Block Diagram-The Rest of the ROMs
8 Other integrated Circuits 118
The 7406 Hex Inverters-The 7407 Hex Buffer/Drivers-The 74LS08 Quad 2-lnput AND Gates-The
74LSOO and 74LS03 NAND Gates-The 74F32 and 74LS32 Quad 2-lnput OR Gates-The 74LS74
Dual 0 Flip-Flop-The 74LS138 1-of-8 Decoder-The 74LS257 Multiplexers-The 74LS373 Octal
Latches-The 74LS244 Octal Drivers-The Transceiver 74F245-The Schmitt Trigger 74LS14-The
4066 Quad Bilateral Switch-The 556 Dual Timer-Other Chip-Like Components
9 The System Block Doagram 150
Block Diagram-The 8502 and Dynamic RAM-The MPU and ROM-MPA and CIA Interface-The
MPU and VIC-The MPU and SID-The MPU and the Video Controller
10 Servicing the logic Gates 167
Decimal and Binary-Hexadecimal-Peek and Poke-Gates-Gate Testing Techniques
11 Servicing Dugotai Registers 188
Flip-Flops-Computing Registers
12 8502 Microprocessor 207
Address and Data Bus Lines-Stack-Arithmetic Logic Unit-Accumulator-Instruction Set-Index
Registers-Flag Register-The 8502 Signals-Testing
13 ZSO Coprocessor 231
Z80 Block Diagram-Z80 Schematic Diagram-Z80 Instruction Set-Z80 Connections-The Com-
puter Won't Start
14 Programmed loguc AlI'lI'ary 240
PLA Internals-PLA Pinout
15 Memory Managemell'llt Unit 249
Bank Contents-MMU Registers-Mode Configuration Register-Ram Configuration Register-The
Page Pointers-Version Register-The MMU Pinout
16 All the Memory Maps 266
The C128 Maps-The C64 Maps-The CP/M Map-PEEK and POKE-MEMORY and FILL
17 The C~ocks 280
Sine Wave to Square Wave-8502 Timing Control-Other Timing Signals-The Z80 Timing-Testing
the Clock
18 Adldll"ess lOata and COll1tro~ BlUIses 298
7
All Those Address Buses-The Data Bus-The 80-Column Display Bus-The Control Lines-Testing
the Bus Lines
19 Complex Interlace Adapters 321
Addressing and Controlling-Internal Data Transfer-Timing-I/O Ports-·PC and -FLAG Pins-
Timers - Real Time Clock - Interrupt Control Register - Serial Data Register - Operation -
CIA 1-CIA2-Testing
20 8564 Video Interface Chip 337
VIC Graphics-VIC Pin-by-Pin Operation-Sprites-Other VIC Features-Light Pen-Video Output
Testing
21 80-Column 8563 Video Controller 354
The 8563 RAM-Pin-by-Pin Checkout
22 Sound Interface Device 364
Pinout-Special Inputs-Operation-Registers-Timing-Testing
23 Inputs and Outputs 379
Checking Out 110 Troubles-RF Modulator
24 The Power Supply 398
First Step-Point-by-Point Checkout
Appendix 406
Index 431
Acknowledgments
I
'd like to thank my wife Lea for rwming inter in Chapter 2. I hope your computing is uninter
ference and fielding interruptions, as usual, while rupted, but should your C128 start acting up, per
I wrote the book. I would also like to thank my fa haps this book will be directly responsible for getting
vorite photographer, my son-in-law, Michael Gor it up and working once again.
zeck, for taking the step-by-step disassembly photos
viii
lest P@ont Charts
U Number Generic Number Given Name Figure Table
U1 6526 Complex Interface Adapter 19-9
U2 4066B Quad Bilateral Switch 8-26 8-10
U3 74LS138 1-of-8 Decoder 8-16
U4 6526 Complex Interface Adapter 19-10
U5 6581 Sound Interface Chip 22-2
U6 8502 Microprocessor 12-20
U7 8722 Memory Management Unit 15-6
U8 74LS08 Quad 2-lnput AND Gate 8-6 8-3
U9 74F32 Quad 2-lnput OR Gate 8-13 8-5
U10 Z80 Microprocessor 13-4
U11 8721 Programmed Logic Array 14-6
U12 74LS373 Octal 3-State D Latch 8-21 8-8
U13 74LS244 Octal 3-State Driver 8-22 8-9
U14 74LS257 Quad 2-lnput Multiplexer 8-19
U15 74LS257 Quad 2-lnput Multiplexer 8-19
U16 74LS14 Hex Schmitt Trigger 8-24
U17 74LS373 Octal 3-State D Latch 8-21 8-8
U18 390059-01 Character ROM 7-3
U19 2016 Color RAM 6-7
U20 4066B Quad Bilateral Switch 8-26 8-10
U21 8564 Video Interface Chip 20-1
U22 8563 Video Controller 21-3
U23 4416 DRAM 21-2
U24 74LS244 Octal 3-State Driver 8-22 8-9
U25 4416 DRAM 21-2
U26 74LS257 Quad 2-lnput Multiplexer 8-19
U27 556 Timer 8-28
U28 8701 Clock 17-16
U29 7406 Hex Inverter Buffer 8-4 8-1
U30 7406 Hex Inverter Buffer 8-4 8-1
U31 74LSOO Quad 2-lnput NAND Gate 8-9 8-4
U32 251913-01 Read Only Memory 7-6
U33 318018-02 Read Only Memory 7-6
U34 318019-02 Read Only Memory 7-6
U35 318020-03 Read Only Memory 7-6
U36 Empty Socket for Function ROM
U37 7406 Hex Inverter Buffer 8-4 8-1
U38-U53 4164 DRAMs 6-1
U54 74LS32 Quad 2-lnput OR Gate 8-13 8-5
U55 74F245 Transceiver 8-23
U56 74LS74 Dual D Flip-Flop 8-14
U57 7407 Hex Buffer 8-5 8-2
U58 74LS03 Quad 2-lnput NAND Gate 8-9 8-4
U59 7812 12 Volt Regulator 24-3
U60 7407 Hex Buffer 8-5 8-2
U61 74LS08 Quad 2-lnput AND Gate 8-6 8-3
U62 74LS244 Octal 3-State Driver 8-22 8-9
U63 7406 Hex Inverter Buffer 8-4 8-1
ix